KR20070030752A - Gage control apparatus - Google Patents

Abstract

SUMMARY OF THE INVENTION The present invention provides a high precision plate thickness control device capable of controlling fluctuation components that cannot be analyzed by frequency analysis, and requiring no plate thickness meter, and not causing a drop in accuracy due to tracking errors.

In the plate thickness control device which is generated in relation to the rotational position of the rolling roll or the supporting roll embedded in the rolling stand for rolling a metal material, and controls the plate thickness fluctuation resulting from roll eccentricity etc., The said rolls 3 and 4 Rolling load variation calculating means for calculating a variation component of the rolling load generated in relation to the rotational position of the roll from the rolling load and the rotational position of the roll, and adding and recording the variation component of the calculated rolling load for each rotational position of the roll. (11) and the rolling roll gap command value which reduces plate | board thickness variation using the variation component of the rolling load for every rotational position of the said roll given from the said rolling load variation calculation means, and calculates the rotation of the said roll Operation amount calculation means 12 for outputting a rolling roll gap command value at a timing selected according to the operation, and the rolling roll gap command value from the operation amount calculation means. Pursuant to a sheet thickness control unit, it characterized in that it includes the roll gap operating means for operating a calender roll gap of the rolling stand.

Sheet thickness meter, rolling roll, roll eccentricity, roll gap operation means, rolling load fluctuation calculation means

Description

Plate Thickness Control Unit {GAGE CONTROL APPARATUS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet thickness control apparatus in a rolling mill of a metal material, and more particularly, to a sheet thickness control apparatus for controlling variation in sheet thickness due to so-called roll eccentricity generated in relation to a rotational position such as a rolling roll. will be.

As one of quality control in thin plate rolling and thick plate rolling, there exists plate | board thickness control (Automatic Gage Control (AGC)) which controls the plate | board thickness of the width direction center part of a rolling material. As a sheet thickness control method, the gauge AGG (Gage meter) using the monitor AGC which feeds back the measured value of the plate thickness meter installed in the rolling mill exit side, and the gauge meter plate thickness estimated from the rolling load or the roll gap. AGC: GM-AGC) and Mill Modulus Control (MMC) by rolling load.

There are some disturbances that hinder the improvement of the plate thickness precision. In hot rolling, it is the temperature fluctuation of a rolling material, and as a disturbance common to hot rolling and cold rolling, tension control by the deterioration of tension control and operator's manual intervention by another control, for example, tension control, is performed. Change in speed and roll gap, roll eccentricity due to poor structure of roll and poor precision of roll polishing, and the like.

Here, roll eccentricity is adopted. Roll eccentricity causes axial vibration mainly when the keyway for oil injection from the oil bearing of the supporting roll is subjected to a rolling load of 2000 to 3000 tons, and roll gap variation occurs in accordance with the roll rotation. However, even in a roll without key grooves, roll gap fluctuations depending on roll rotation occur due to any other cause.

Moreover, also in the case of the so-called 4Hi mill comprised of 4 rolls of which the rolling rolls are two top and bottom, and the support rolls are the two top and bottom, 6 rolls with the top and bottom of the rolling rolls, the top and bottom of the middle rolls, and the top and bottom of the support rolls up and down Also in the case of the so-called 6Hi mill comprised by or the other case, the following can be considered the same. Representatively, a rolling roll is called a work roll (WR) and a support roll as rolls other than a rolling roll, and it is called a back up roll (BUR).

The disturbance depending on the roll axial vibration such as the roll eccentricity cannot be detected by the roll gap detector, but appears in the rolling load. For this reason, it becomes large disturbances, such as said MMC, GM-AGC.

In order to reduce the disturbance which depended on roll axial vibrations, such as this roll eccentricity, roll eccentric control is conventionally performed. The roll eccentric control is mainly known in the following two methods.

(A) The roll eccentric frequency is analyzed by contacting the top and bottom rolls before rolling, applying a constant load (in a kis-roll state) to rotate the rolls, and converting the detected load into a fast Fourier transform. During rolling, the roll eccentricity of the analyzed frequency is generated, and the roll gap operation amount which reduces this is output (patent document 1, 2).

(B) If a thickness gauge is installed on the exit side of the rolling mill, the thickness variation can be measured by the thickness gauge. For this reason, when a roll gap is operated according to plate | board thickness dispersion | variation with respect to which rotational position of a roll the value measured with the plate | board thickness meter is connected, plate | board thickness variation by roll eccentricity can be reduced (patent document 3). ).

[Patent Document 1] Patent No. 1596084 (Japanese Patent Publication No. 2-18170)

[Patent Document 2] Patent No. 1814074 (Japanese Patent Publication No. 5-21651)

[Patent Document 3] Japanese Unexamined Patent Publication No. 2002-282917

The above-described control methods (A) and (B) have the following drawbacks.

[Method (A)]

As mentioned above, even if it is a roll eccentricity, the cause cannot be identified. In general, roll eccentricity is often caused by a supporting roll, but may also occur due to the polishing state of the rolling roll or the like. In addition, it is assumed that the variation component of the load generated in relation to the roll rotation position is a sinusoidal wave. Frequency components that are two times or three times higher than the lowest frequency, the so-called fundamental frequency, may appear, and it is difficult to reduce the disturbance of which frequency. In addition, the amplitude of the load fluctuation amount detected in the kiss roll state generally differs from the amplitude of the load fluctuation amount detected at the time of rolling.

[Method (B)]

The rolling mill to which the control of the method (B) can be applied needs to have a plate thickness meter installed at the exit side. For example, a hot plate tandem rolling mill composed of 7 stands is likely to show plate thickness variation due to roll eccentricity of 5, 6, and 7 stands, which are the rear ends, as a product plate thickness variation. It is installed only at the exit side.

For this reason, roll eccentricity of 5 and 6 stands cannot be controlled. In addition, it is necessary to accurately track the rolling material from the rolling stand to the plate thickness meter on the exit side thereof, and it is necessary to accurately collect the rolling material speed. The rolling material speed can be calculated by taking the roll rate into consideration in the roll circumferential speed. However, the roll rate is predicted and an error is included for the roll circumferential speed that can be measured. For this reason, an error is included in a rolling material speed and tracking error tends to occur.

Moreover, when a rolling load changes with respect to a roll rotation position, such as roll eccentricity, there exists a following problem. In general, the AGC calculates the gauge meter plate thickness to estimate the exit plate thickness of the rolling stand, and controls the plate thickness to match the target value or the like.

By the way, when there exists a roll eccentricity etc., this gauge meter plate thickness is not calculated correctly. The reason for this is as follows. For example, if a roll gap is generated due to roll eccentricity or the like, the actual exit plate thickness becomes thick, but the rolling load becomes small because of the roll gap opening. For this reason, the mill elongation becomes small on the calculation of the gauge meter plate thickness, and the gauge meter plate thickness becomes small. This is explained by gauge meter equation (1) below.

[Equation 1]

(1)

(One)

here,

: 롤 편심 등에 의한 게이지 미터 판 두께의 변화[mm]

: Change in gauge meter plate thickness due to roll eccentricity [mm]

: 롤 편심 등에 의한 롤 갭의 변화[mm]

: Change in roll gap due to roll eccentricity [mm]

: 롤 편심 등에 의한 압연 하중의 변화[kN]

: Change in rolling load due to roll eccentricity [kN]

: 밀상수[mm/kN]

: Wheat constant [mm / kN]

However, in calculation, ΔS _RE is not detectable and ΔS _RE = 0, but the change in rolling load is ΔP _RE <0 because true ΔS _RE is the opening direction, that is, the value of +. Therefore, the change in the gauge meter plate thickness is given by Equation (2) below.

[Formula 2]

(2)

(2)

That is, the influence of the change in the rolling load in relation to the roll rotational position such as roll eccentricity is estimated completely opposite to the calculated gauge meter thickness.

However, it is impossible to detect a change in the roll gap due to the roll eccentricity and the like, and an operation with good precision is not desired beyond this.

The present invention has been devised in consideration of the above-described point, and can control the fluctuation component that cannot be analyzed by frequency analysis, and also does not require a plate thickness meter, and does not cause a deterioration of accuracy due to a tracking error. It is an object to provide a thickness control device.

In order to achieve the above object, in the present invention,

In the plate thickness control apparatus which controls the plate | board thickness fluctuation resulting from roll eccentricity etc. which generate | occur | produced with respect to the rotational position of the rolling roll or support roll comprised integrally with the rolling stand for rolling a metal material,

Rolling load fluctuation which calculates the fluctuation component of the rolling load which generate | occur | produced with respect to the rotational position of the said roll from the rolling load and rotation position of the said roll, and adds and records the calculated fluctuation component of the rolling load for every rotational position of the said roll. Calculation means,

The rolling roll gap command value which reduces plate | board thickness variation is calculated using the variation component of the rolling load for every rotational position of the said roll given from the said rolling load variation calculation means, and it selected the timing according to the rotation of the said roll. Manipulated value calculating means for outputting a rolling roll gap command value at

It is provided with the plate thickness control apparatus provided with the roll gap operation means which operates the rolling roll gap of the said rolling stand based on the rolling roll gap command value from the said operation amount calculation means.

As described above, the present invention records and records the rotational position of the rolling roll or the support roll and the variation component of the rolling load, and reduces the plate thickness variation by using the variation component of the rolling load for each rotational position of the roll. Since a rolling roll gap command value is calculated | required and a rolling roll gap is operated by this rolling roll gap, a more precise control result can be obtained than the control system of the rolling load fluctuation by roll eccentricity etc. which were conventionally performed. In other words, it is possible to calculate and control the fluctuation components that cannot be analyzed by frequency analysis, and to realize the control that does not require a plate thickness meter due to the structure of the equipment, and does not cause a decrease in accuracy due to tracking errors.

In addition, in the calculation of the gauge meter plate thickness which was incorrect when there was a rolling load variation due to roll eccentricity or the like, an accurate gauge meter plate thickness can be obtained by performing the correction according to the present invention. For this reason, the AGC function using the gauge meter plate | board thickness becomes high precision, and plate | board thickness precision also improves.

In addition, the calculation which the influence of the rolling load which generate | occur | produced in connection with a roll rotation position was estimated to the contrary is calculated suitably by performing the plate | board thickness control by this invention, and the other plate | board thickness control function operates suitably. It becomes possible.

1 is a view showing the overall configuration of an embodiment of the present invention.

2 is a view showing a concept of a rolling load in one embodiment of the present invention.

3 is a diagram showing a relationship between a circumferential length division of a support roll used in the present invention and a rolling roll;

4 is a view showing an example of a method for calculating a rolling load variation due to roll eccentricity and the like in a supporting roll.

5 is a view showing another example of a method for calculating the rolling load variation due to roll eccentricity or the like in the support roll.

FIG. 6 is a block diagram showing details of the configuration of the embodiment shown in FIG. 1; FIG.

Fig. 7 is a characteristic diagram showing the results of the control according to the present invention.

Explanation of symbols for the main parts of the drawings

1 rolled material 2 rolling mill housing

3: rolling roll 4: supporting roll

5: rolling down device 6: rolling load detector

7: roll rotation speed detector 8: roll reference position detector

9 roll gap detector 11 rolling load fluctuation calculation means

12: manipulated variable calculating means 13: roll gap operating means

111: rolling load holding means 112: average value calculation means

113: Subtractor LM: Limiter

SS, SW: Switch Σ: Adder

P: rolling load ΔP _A : Deviation of rolling load

ΔS: Roll gap correction amount

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Example 1

1 shows the overall configuration of a first embodiment of the present invention. In this FIG. 1, the rolled material 1 is arrange | positioned at the center part of the rolling mill housing 2, and is rolled by the upper and lower rolling rolls 3 with the gap and speed adjusted suitably, and the desired plate thickness at the exit side It becomes

The rolling roll 3 is supported by the support roll 4 provided behind, and the curvature of the roll width direction is made small. The supporting roll 4 is supported by the rolling mill housing 2, and has a structure which can endure the rolling load for rolling the rolling material 1. As shown in FIG.

The gap between the upper and lower rolling rolls 3 is adjusted by the pressing device 5. There are two types of the reduction device 5, namely, by electric motor control (referred to electric reduction) and by hydraulic control (referred to hydraulic reduction). The latter side tends to obtain a high speed response. In general, in order to control disturbances such as roll eccentricity, a high-speed response is required, and hydraulic pressure reduction is employed, so an example of hydraulic pressure reduction will be described below.

Then, the rolling load is detected by the rolling load detector 6. The rolling load detector 6 is buried between the rolling mill housing 2 and the rolling reduction device 5, and a load cell LC for directly measuring the rolling reaction force or a load inverted from pressure detection under hydraulic pressure reduction. This is used.

Rotation of the rolling roll 3 is detected by the roll rotation speed detector 7. The roll speed detector 7 is attached to the shaft of the rolling roll 3 or the electric motor (not shown) which drives the rolling roll 3, and detects the rotation speed of the rolling roll 3.

The roll reference position detector 8 is provided in the support roll 4 provided behind the rolling roll 3, and a reference position is detected by a proximity switch etc. every time the support roll 4 rotates one rotation. Moreover, the roll gap detector 9 is provided between the support roll 4 and the reduction apparatus 5, and detects the gap of the rolling roll 3 indirectly.

FIG. 2 is a diagram showing the concept of the measured rolling load, and a method of calculating the rolling load variation will be described using this FIG. 2. When there exists a roll eccentricity etc., the rolling load fluctuation component by roll eccentricity etc. superimposes on the rolling load fluctuations other than roll eccentricity etc., for example, the rolling load fluctuation which arises by temperature change and plate thickness change.

These two are separated, and the rolling load fluctuation by roll eccentricity etc. is controlled by the control apparatus which concerns on this invention, and rolling load fluctuations other than roll eccentricity etc. are controlled by MMC, GM-AGC, etc.

3 shows the relationship between the circumferential length division of the support roll 4 (BUR) and the rolling roll 3 (WR). In this FIG. 3, there is a position scale in which the entire circumferential length of the support roll 4 is divided equally n in the relationship between the rolling roll 3 and the support roll 4, and does not rotate on the outermost side of the support roll 4. Assuming that the reference position is O, the number is given to the (n-1) th position.

For example, the position θ _B of the divided position 3 of the support roll 4 is

θ _B3 = 3 × 360 / n [degrees]

to be. And the position of the rolling roll 3 in FIG. 3 is a rolling roll position whose ( theta) wo corresponds to the reference position of the support roll 4, and ( theta) w rotates the rolling roll 3 and the support roll 4 simultaneously. It is a position corresponding to the position θ _B of the supporting roll 4 after the removal.

In order to perform this detection, sensors, such as a proximity switch, are embedded in one place of the support roll 4, and the roll reference position detector 8 is provided in the reference position of the position scale which does not rotate. And when the sensors, such as the proximity switch provided in one place of the support roll 4, reached the reference position of the position scale which does not rotate, it can be recognized that the support roll 4 passed the reference position.

Rolling loads are separately recorded and recorded in the divided position from the reference position 0 on the periphery of the support roll 4 to the position n-1. Generally, a value of about n = 30-40 is used.

4 shows an example of a method of calculating the rolling load variation due to the shape in which the rolling load P changes with the change of the rotational position of the supporting roll, the roll eccentricity, and the like.

4, the position of the support roll BUR which changes with passage of time on the horizontal axis | shaft is taken, and the rolling load is taken to the vertical axis | shaft. And the change of the rolling load between two rotations of the support roll BUR has shown the mountain and two grains.

That is, in the first rotation, the rolling load P ₁₀ is at the reference position O (time T ₁₀ ), and the rolling load P ₁₁ is at the position 1 of the support roll (time T ₁₁ ). a support roll position (2) (the time (T _12)), the rolling load (P _12), and the support roll position (3) (time point (T _13)), the rolling load (P ₁₃₎ in the. Similarly, even in the next one rotation, the rolling load changes depending on the position of the support roll.

Thus, in the support roll reference position O, as the rolling load is P ₁₀ and the positions of the supporting roll advance to 1, 2 and 3, the rolling loads are P ₁₁ , P ₁₂ , P ₁₃ ... To change. When the rolling load at the support roll position n-1 and the rotational position at one rotation was also able to extract P ₂₀ , P ₁₀ and P ₂₀ were connected in a straight line, and this straight line was used to change the rolling load variation due to roll eccentricity. May be regarded as excluded rolling load.

Therefore, the rolling load fluctuations due to the roll eccentricity etc. according to the rotation of the supporting roll are measured by the measured rolling loads P ₁₀ , P ₁₁ , P ₁₂ , P ₁₃ ,. , Can be calculated as P _20, respectively, and the car (差) with a straight line, that is, O, ΔP _{11, 12} ΔP, ΔP _ij, ΔP _{1n -1.}

5 shows another example of a method in which the rolling load P changes in accordance with the change in the rotational position of the supporting roll, and the method for calculating the rolling load variation due to the roll eccentricity.

The change in the actual rolling load value is often a result of noise in addition to the rolling load fluctuation due to the roll eccentricity or the like, the rolling load fluctuation due to the temperature fluctuation, sheet thickness fluctuation, tension fluctuation or the like. Therefore, it is the rolling load (P ₂₀₎ of the rolling load at the time (始點) in the method shown in Fig. 4 (P ₁₀₎ and the end point (終點) is not clear, it is certain that it is difficult cases.

In order to cope with such a case, it is assumed that the one rotation time of the support roll is not long, and the change of P ₁₀ and P ₂₀ is hardly large. Then P ₁₀ , P ₁₁ ,... , N average values of P _1n-1 are taken, and the difference between the measured rolling loads (P ₁₀ , P ₁₁ , P ₁₂ , P ₁₃ ,..., P ₂₀ ) and the average of these values is determined by a roll eccentricity or the like. It can be regarded as a rolling load variation.

The advantage of this method is to extract the performance value of the rolling load until the (n-1) division, and is resistant to fluctuations caused by noise or the like. In addition, the performance value of a rolling load may perform a filtering process in order to further reduce the influence of a noise.

FIG. 6 is a roll gap operation means 12 which calculates a roll gap operation amount and determines an operation amount using the value of the rolling load in each position of the support roll computed by the rolling load variation calculation means 11 (FIG. 1). The structure of the board | substrate thickness control apparatus provided with FIG. 1 is shown.

First, the outline | summary of the structure of FIG. 6 is demonstrated. In the rolling load fluctuation calculation means 11, the load detection signal P is applied to the positions 0, 1, 2,... , P ₀ , P ₁ , P ₂ ,... , P _j ,… , P _{n -2} , P _{n -1} , and are given to the subtractor 113. In the subtractor 113, the difference with the average value (1 / nΣP _j (j = 1, 2, ..., (n-1))) calculated by the average value calculating means 112 is calculated separately, and the limiter LM1 Is given by

In the limiter LM1, the output of the subtractor 113 is given, the upper and lower limits are checked, and sent to the adder Σ via the switch SS. The output of the adder Σ is sent to the roll gap operating means 12 as the deviation ΔP _A of the rolling load through the switch SW and the gate G. FIG.

In the roll gap operating means 12, the roll gap correction amount ΔS is requested based on the given deviation ΔP _A , and is sent to the reduction device 5 (FIG. 1), and the roll gap amount by MMC or GM-AGC. In addition, the operation amount is added or decreased.

Next, the detail of the structure of FIG. 6 is demonstrated. In FIG. 6, the apparatus structure using the average value shown in FIG. 5 is shown, and this apparatus uses the linear interpolation between the starting point and the end point shown in FIG. It can also be applied simply to the calculation method.

And, 6, the rolling load holding means 111 is the angular position of the support roll (0, 1, 2, ..., nl), the rolling load (P _0, P _1, P _2, ..., P _j, in ..., P _{n -2} , P _{n -1} ) is maintained during the rotation of the support roll by one rotation, and at the time when the position n-1 is reached, the average value, that is, 1 / nΣP _j (j = 1, 2, ..., (n-1)) is calculated. Rolling load (P ₀ , P ₁ , P ₂ ,…, P _j ,…, P _{n -2} , P _{n -1} ) at each position (0, 1, 2,…, n-1) of this support roll And the difference between these average values (1 / nΣP _j (j = 1, 2, ..., (n-1))) are referred to as rolling load variations due to roll eccentricity or the like.

In this case, instead of finding the difference from the average value (1 / nΣP _j (j = 1, 2, ..., (n-1))), the equation of the straight line from P ₀ at the starting point and P _n at the end point May be calculated and the difference between the straight line and the rolling load (P ₀ , P ₁ , P ₂ ,..., P _j ,..., P _{n -2} , P _{n -1} ) at each position may be calculated.

The upper and lower limits of the rolling load fluctuation due to roll eccentricity and the like at each position of the supporting roll are checked by the limiter 1, and the average value (1 / nΣP _j (j = 1, 2, ..., (n-1))) At the end of the calculation, the switch SW is simultaneously turned on to add the deviation (ΔP ₀ , ΔP ₁ ,..., ΔP _{n -1} ) to the adders (Σ ₀ , Σ ₁ , Σ ₂ ,. ,? _J ,..., P _{n -2} , P _{n -1} ), and added by the following equation (3).

(3)

(3)

here,

Z: Addition

k: addition count

j: 1 to n-1

The adder Σ is zero-cleared before the rolling material is rolled, and each time the calculation of the average value at which the support roll is rotated is finished, the deviation of the rolling load is added each time. This procedure is performed by the limiter LM1, the switch SS and the adder Σ.

In addition, as shown in Equation (4) below, it is also effective to introduce the forgetting coefficient (b) to reduce the influence of the accumulated value in the past and to greatly evaluate the influence of the rolling load variation close to the present time.

(4)

(4)

The switch SW takes out one deviation of the added rolling load from the adder Σ corresponding to the rotational position of the support roll. For example, looking at the reference position 0, when the support roll passes the reference position O, only the switch SW ₀ is turned on and the deviation ΔP _A0 of the rolling load from the adder Σ ₀ It is taken out.

When the support roll reaches the position ₁ , only the switch SW ₁ is turned on, and ΔP _A1 is taken out from the adder Σ ₁ . This operation is repeatedly performed by the take-out switch SW of the rolling load fluctuation value by the roll eccentricity etc. corresponding to the position of a support roll.

Incidentally, the addition at each position can be easily guided from the general control side. That is, as in the control object of the present invention, when there is no integrator in the control object, it is reasonable to put the integrator on the controller side and remove the normal deviation from the control side. It is necessary as an adder, not an integrator, because the controlled object is a discrete value system, not a continuous system.

The roll gap correction amount which is the operation amount is calculated by the following equation (5) in the roll gap operation means 13 (FIG. 1) which compensates the rolling load fluctuation value due to the roll eccentricity or the like.

[Equation 3]

(5)

(5)

here,

M: Wheat constant [ton / mm]

Q: Plasticity coefficient of rolled material [ton / mm]

K _T : adjustment factor

ΔS: Roll gap correction amount [mm]

ΔP _A : Variation of rolling load (rolling load fluctuation due to roll eccentricity, etc.) [mm]

The roll gap operation means 13 checks the roll gap correction amount (DELTA) S by said formula (5) up and down with the limiter LM2, and adds it to roll gap amounts, such as MMC and GM-AGC, and reduces it. It gives to the apparatus 5 (FIG. 1).

In this case, depending on the response of the pushing device 5, time delay may not be negligible. For example, if the response of hydraulic pressure reduction is 100% when the cutoff frequency is 60 rad / sec, the time for reaching 95% is 0.05 sec.

In addition, a calculation time delay etc. may be added to this. One rotation of the support roll may be around 0.5 to 1 second, and since the time delay of 0.05 seconds corresponds to 1/10 to 1/220, there may be a great influence.

Therefore, this problem can be solved by speeding up the timing of calculating the roll gap correction amount by the manipulated variable calculating means 12. For example, in FIG. 3, when the division number n is 40 and one rotation of a support roll is 0.8 second, the time progressed from one position to the next position is 0.02 second. At this time, if there is a time delay of 0.05 seconds, the roll gap correction means 13 is given to the roll gap correction amount prior to 2.5 revolutions.

7 shows the effect of the reduction control according to the present invention. When the control according to the present invention is on, the variation in the rolling load is small, and after the off, the variation is large. In addition, although the said Example is based on rotation of a support roll, you may refer to a rolling roll as a reference.

Next, the correction method of a gauge meter plate thickness calculation is demonstrated. Regarding the calculation of the gauge meter plate thickness when the control of the present invention is performed, the plate thickness of the jeans is calculated by the following equation (6), and it is said that the influence of the rolling load variation due to the roll eccentricity can be separated.

[Equation 4]

                                                                    (6)

here,

: 진의 판 두께[mm]

: Plate thickness of jeans [mm]

: 진의 롤 갭[mm]

: Roll gap of jeans [mm]

: 압연 하중 실적 값[kN]

: Rolling load performance value [kN]

: 롤 편심 등에 의한 압연 하중 변동에 의한 것 이외의 롤 갭(측정 가능)[mm]

: Roll gap other than due to rolling load fluctuation due to roll eccentricity (measurable) [mm]

: 롤 편심 등에 의한 압연 하중 변동 이외의 압연 하중[mm]

: Rolling load [mm] other than rolling load fluctuation due to roll eccentricity

: 롤 편심 등에 의한 압연 하중 변동에 의한 롤 갭의 변화[mm]

: Change in roll gap due to rolling load variation due to roll eccentricity [mm]

: 롤 편심 등에 의한 압연 하중 변동[kN]

: Rolling load fluctuation due to roll eccentricity [kN]

: 밀상수[mm/kN]

: Wheat constant [mm / kN]

The roll gap is said to have a large + or a large value in the opening direction, and the magnitude of the rolling load remains the same. At this time, if there is no rolling load fluctuation due to roll eccentricity or the like, the plate thickness of the jeans is

[Equation 5]

(7)

(7)

On the other hand, the gauge meter plate thickness is represented by Equation (8) below,

[Equation 6]

(8)

(8)

to be.

The rolling load fluctuations due to roll eccentricity compensation according to the present invention was 10O% if high (the compensation amount ΔS = ΔS ^C _{RE RE), RE} is the ΔP = 0. And the gauge meter plate thickness is as shown in the following formula (9),

[Formula 7]

(9)

(9)

It becomes Therefore, in order to match the gauge meter plate thickness with the plate thickness of the gin, it is necessary to apply a compensation amount ΔS _RE ^C to the gauge meter plate thickness.

Next, according to the present invention, it is assumed that the rolling load fluctuation due to the roll eccentricity or the like compensates for r (O <r <1). That is, as shown in the following formulas (10) and (11),

Equation 8

(10)

10

(11)

(11)

When placed, the plate thickness of the jeans can be expressed by Equation (12) below.

[Equation 9]

(12)

(12)

Here, since a rolling load can be detected, it summarized as one parameter P ^ACT .

On the other hand, in gauge meter plate thickness,

Equation 10

                                                                   (13)

to be. To match this equation (13) with equation (12),

[Equation 11]

(14)

(14)

You need to add

That is, in the case of carrying out the present invention, in order to calculate the gauge meter plate thickness, the index (r) showing the effect of the present invention is considered in the roll gap (command value or performance value) compensated by the present invention, By adding the term which can be represented by the form of (14) to the gauge meter plate thickness calculation formula, a favorable plate thickness with a precision closer to that of the true plate is obtained.

About the index r which shows the effect of this invention, this invention can be implemented several times, the effect can be grasped quantitatively, and r value can be determined.

According to the present invention, the plate thickness control of the rolling mill can control a fluctuation component that cannot be analyzed by frequency analysis, and does not require a plate thickness meter, and does not cause a decrease in accuracy due to a tracking error. Provide thickness control devices.

Claims (8)

In the plate thickness control apparatus which is produced in relation to the rotational position of the rolling roll or support roll embedded in the rolling stand for rolling a metal material, and controls the plate thickness fluctuation resulting from roll eccentricity etc., Rolling load fluctuation which calculates the fluctuation component of the rolling load which generate | occur | produced with respect to the rotational position of the said roll from the rolling load and rotation position of the said roll, and adds and records the calculated fluctuation component of the rolling load for every rotational position of the said roll. Calculation means, The rolling roll gap command value which reduces plate | board thickness variation is calculated using the variation component of the rolling load for every rotational position of the said roll given from the said rolling load variation calculating means, and the timing selected according to the rotation of the said roll is calculated. Manipulated value calculating means for outputting a rolling roll gap command value at And a roll gap operation means for manipulating the rolling roll gap of the rolling stand based on the rolling roll gap command value from the operation amount calculation means. The method of claim 1, And said rolling load variation calculating means corrects a reference position every one rotation of said roll when detecting said rotational position of said roll. The method of claim 1, The rolling load variation calculating means records the load per one revolution of the roll for each rotation position, linearly interpolates the rolling loads at the start and end of one revolution after completion of one revolution and linearly interpolates the rolling load value. And a rolling load for each rotational position, and calculating a variation component of the rolling load generated in relation to the rotational position. The method of claim 1, The rolling load variation calculating means records the load per one rotation of the roll for each rotation position, and after completion of one rotation, compares the average value of the rolling load between one rotation and the rolling load for each rotation position, Calculating the variation component of the rolling load generated in association with the sheet thickness control apparatus. The method of claim 1, The rolling load variation calculating means integrates the variation component of the calculated rolling load for each rotational position of the roll, calculates an integrated value of the rolling load corresponding to the rotational position of the roll at the current control time, And said manipulated value calculating means calculates a gap command value of said rolling roll so as to suppress the variation in sheet thickness caused by the integrated value of this rolling load. The method of claim 5, The rolling load fluctuation calculating means, when there is a time delay in the roll gap operation amount, goes back to the rotational position of the roll corresponding to the delay time from a rolling load integration value corresponding to the rotational position of the roll at the current control time. The plate thickness control apparatus characterized by ascending and calculating the integrated value of the rolling load. The method of claim 5, And said rolling load variation calculating means adds up to reduce the influence of the first accumulated value when integrating the variation component of said rolling load. The method according to any one of claims 1 to 7, And said manipulated value calculating means corrects a gauge meter plate thickness using a ratio of reducing plate thickness variation, a rolled roll gap command value, or a roll gap based on the command value.

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